Abstract. In recent years, 3D printing technology has been used in all walks of life because of the rapid development of 3D printing technology. Due to the pursuit of personalization, color 3D printing technology has developed rapidly since its appearance. This paper first summarizes the research development and application status of FDM color 3D printing. Starting with the printing process and technical principle of FDM color 3D printing technology, the shortages and main contradictions of the existing color printing nozzles are summarized. The design principle, structure, merits and demerits of the multi-color printing nozzle are analyzed, and some improvements are proposed for the current nozzle. The goal is to take color 3D printing a step further.